Catfish and koi

[Brian Hillestad]

I have an 800 gallon tank with 12-14 koi in there.  I also have 5 small catfish.  They worked well to clean out the bottom of the tank, but now they seem to be attacking the koi.  I have had 3 die in the last few days.  Shall I separate them or can koi and catfish coexist?

[Steve R]

what species of catfish. Iv never heard of catfish beating up other fish and koi can be tough thats most odd.